MAUDE Adverse Event Report: ROCHE DIAGNOSTICS COBAS C 111 ANALYZER WITH ISE; CLINICAL CHEMISTRY ANALYZER

Catalog Number	04777433001
Medical Device Problem Codes	Incorrect, Inadequate or Imprecise Result or Readings (1535); Low Test Results (2458); Non Reproducible Results (4029)
Health Effect - Clinical Code	No Clinical Signs, Symptoms or Conditions (4582)
Date of Event	12/04/2025
Type of Reportable Event	Malfunction
Event or Problem Description
The initial reporter stated they received discrepant results for one patient sample tested with the sodium electrode on a cobas c 111 with ise.The customer stated they have been having ongoing issues with the ise tests on the analyzer.The patient sample initially resulted in a sodium value of 131 mmol/l.The customer had been monitoring results due to ongoing issues and questioned the low value.The sample was repeated on a second analyzer, resulting in a value of 140 mmol/l.The repeat value was deemed correct.
Additional Manufacturer Narrative
The serial number of the c111 analyzer is (b)(6).The customer changed the sodium electrode but could then not get the system to re-start.They received mix tower alarms.The investigation is ongoing.
Additional Manufacturer Narrative
Medwatch fields d1, d2, d4, g1, and g4 have been updated.
Additional Manufacturer Narrative
Medwatch sections d.Device identification, d.Manufacturer info, g contact office-manufacturing site (continued g1) and medwatch field g4 pma / 510k (premarket numbers) updated.The field service engineer inspected the module and determined that defective ion-selective electrode (ise) tubes and a defective liquid level detection (lld) cable caused the event.He replaced these parts, as well as the transfer head cable detection kit and sample probe.He also adjusted the reference pinch valve and activated the electrodes.He verified the analyzer's performance by a successful reinitialization, lld frequency tests, calibrations, and qcs.The customer has not reported any other issues after the service.The investigation determined that the service actions resolved the issue.

• Brand Name: COBAS C 111 ANALYZER WITH ISE
• Common Device Name: CLINICAL CHEMISTRY ANALYZER
• Manufacturer (Section D): ROCHE DIAGNOSTICS; 9115 hague road; indianapolis IN 46250 0457
• Manufacturer (Section G): ROCHE INSTRUMENT CENTER AG TEGIMENTA; forrenstrasse; rotkreuz 6343 ; SZ 6343
• Manufacturer Contact: natalie catton ; 9115 hague road; indianapolis, IN 46250-0457
• MDR Report Key: 23869997
• Report Number: 1823260-2025-05300
• Device Sequence Number: 4438159
• Product Code: JJE
• UDI-Device Identifier: 04015630924769
• UDI-Public: 04015630924769
• Combination Product (Y/N): N
• Initial Reporter State: WI
• Initial Reporter Country: US
• PMA/510(K) Number: K071211
• Number of Events Summarized: 1
• Summary Report (Y/N): N
• Serviced by Third Party (Y/N): Unknown
• Reporter Type: Manufacturer
• Report Source: Health Professional,User Facility
• Initial Reporter Occupation: Other Health Care Professional
• Type of Report: Initial,Followup,Followup
• Report Date (Section B): 03/19/2026

1 Device was Involved in the Event

1 Patient was Involved in the Event

• Is this an Adverse Event Report?: No
• Is this a Product Problem Report?: Yes
• Operator of Device: Health Professional
• Device Expiration Date: 10/31/2025
• Device Catalogue Number: 04777433001
• Device Lot Number: 31251847
• Was Device Available for Evaluation?: Yes
• Is the Reporter a Health Professional?: Yes
• Type of Report(Section G): Follow-Up
• Initial Date Received by Manufacturer: 12/08/2025
• Supplement Date Received by Manufacturer: 01/06/2026; 02/27/2026
• Initial Report FDA Received Date: 12/22/2025
• Supplement Report FDA Received Date: 01/29/2026; 03/19/2026
• Was Device Evaluated by Manufacturer? (Y/N): Yes
• Is the Device Labeled for Single Use? (Y/N): No
• Is This a Single-Use Device that was Reprocessed and Reused on a Patient? (Y/N): No
• Patient Sequence Number: 1
• Patient Age: 41 YR
• Patient Sex: Female